Thursday, June 15, 2006

China's GPS: Military Threat?

Peter B. de Selding hit the front page of Space News the other day with a scoop about a Chinese plan to build a 24-satellite navigation network, called Compass, in roughly the same orbit as the American and European sat-nav systems, GPS and Galileo. But there’s more: the Chinese are apparently “threatening” to use an encrypted signal for military ops that would actually overlay – and maybe interfere with – "M-Code," the Pentagon's GPS broadcast. That's the signal that keeps everything from precision bombs to flying drones on track.

You might remember that the Pentagon had a right royal hissy fit when the Europeans proposed to overlay Galileo’s encrypted signal on the M-code, because under those circumstances the U.S. military wouldn’t be able to jam Galileo during any hostilities without blocking its own ability to access the GPS signal. So, you would figure collective hair would be on fire over at the five-sided building at the news of the Chinese plan, right?

Well, maybe and maybe not. Turns out this jamming biz is not as simple as it sounds.